RZD has ordered 40 type 3ES4K locomotives for operation on the October Railway linking St Petersburg with Baltic Sea ports and the Severo-Kavkazskaya Railway, which connects the Black Sea resort of Sochi with the rest of the country.

The 3ES4K is a triple-section version of the 2ES4K double-section locomotive. It is designed for operation on lines electrified at 1.5kV dc. The 3ES4K is powered by 12 800kW dc traction motors which produce a total output of 9.3MW and a continuous rating of 8.6MW, compared with 6.2MW and 5.74MW respectively for the 2ES4K, and it is able to haul freight train of up to 6000 tonnes. The tractive effort of the 3ES4K is 651kN compared with 434kN for the 2ES4K. The new BoBo BoBo BoBo locomotive is 52.5m long.